In an email to staff and families Monday afternoon, Shawnee Mission Schools Superintendent Mike Fulton said that all middle and high schoolers in the district will return to remote learning after Thanksgiving, starting Monday, Nov. 30.The announcement said secondary students would remain in remote learning through at least Jan. 22, when the first semester ends.For now, elementary students will continue to attend school in person if they have chosen that learning mode, though Fulton left open the possibility that they, too, could be switched to virtual learning in coming weeks.Why it matters: The move comes as new cases of COVID-19 skyrocket in Johnson County. Last week, at a special board of education meeting, district officials indicated staffing shortages created by the pandemic were making it difficult to continue holding in-person classes for all students.Fulton noted this in his email Monday.“We have reached the point where we are unable to fully staff all of our buildings, and need to make a change,” he wrote. “We have a rising number of employees who are in quarantine or isolation, which is impacting our ability to staff buildings at all levels. Implementing remote learning for our secondary students will allow us to shift critical resources such as substitutes to the elementary level, giving us the best opportunity to keep elementary students in-person.”The district’s online COVID-19 dashboard, as of Monday, showed 180 staff members either in active isolation — meaning they have tested positive, are presumed positive or are showing symptoms of the disease — or are in active quarantine after having been possibly exposed to a positive case.In addition, more than 820 students are either in active isolation or quarantine.The bigger picture: New cases have exploded in Johnson County over the past month. The county’s COVID-19 dashboard showed the incidence rate for new cases on Monday had risen to 760 per 100,000 residents, and the county’s percent positivity stood at 16.5%. Both metrics suggest widespread community transmission.In his message Monday, though, Fulton said that Shawnee Mission officials continue to see little transmission happening in schools themselves.“We continue to see schools doing an excellent job of implementing mitigating factors such as social distancing, mask-wearing, hand washing, and completing daily COVID-19 assessments,” he said.On Friday, the Johnson County Board of County Commissioners issued a new public health order, imposing new limits on businesses and organizations that took effect Monday.Blue Valley Schools has also announced that secondary students in that district would also revert to remote-only learning after Thanksgiving and stay in that mode through at least Dec. 22.What happens next: Fulton suggested elementary students could also be switched from in-person learning to remote in the near future if COVID-19 conditions in Johnson County continue to worsen.“For elementary parents, it is very important that you take the above into consideration as you plan in the weeks ahead,” he wrote, referencing the importance of continuing to mask, socially distance and avoid large gatherings. “In the interest of student and staff safety, we will not hesitate to move from in-person to remote learning if health conditions and/or staffing limitations require us to do so.”If such a change is made, he said, the district would try to give parents 14 days advanced warning.